Floor surfacing machine



July 1, 1969 J. M. LOMBARDO ETAL FLOOR SURFACING- MACHINE Sheet 1 of 2 Filed Jur 1 e 26, 1967 INVENTORS JOHN M. LOMBARDO BY CLARENCE W. FRIESEN LOUIS M. Lama/moo 9% Q. $1M

u y 1, 1969 J. M. LOMBARDO ETAL 3,452,486

FLOOR SURFACING MACHINE Filed June 26, 1967 Sheet 5 of 2 Z :-7 FIG. 5.

I 76 h 22 I02 98 IIIIJIJ g K 0 INVENTORS v Jar-m M. LOMBARDO 56 CLARENCE W. FRIESEN BY Lou/5 M- LOMBARDO United States Patent Office 3,452,486 Patented July 1, 1969 FLOOR SURFACING MACHINE John M. Lombardo, North Hollywood, Clarence W. F riesen, Alhambra, and Louis M. Lombardo, Van Nuys, Calif., assignors to Terrazzo Supply Corporation, North Hollywood, Calif., a corporation of California Filed June 26, 1967, Ser. No. 648,718

Int. Cl. B241) 23/02 U.S. Cl. 51177 6 Claims ABSTRACT OF THE DISCLOSURE A support frame for a pair of fore and aft rubbing discs has mass loading Weights selectively and variably disposed by way of bracket fixture between the axes of the shafts of the discs; a horizontally disposed power shaft drives one of the disc shafts through a right-angle drive.

Background of the invention This invention relates in general to floor surfacing machines and is concerned more particularly with machines of the type used in the finishing of terrazzo tile floors.

In machines of this type, of which the prior art is exemplified in Patent No. 2,793,476, it has been customary to provide a pair of rubbing discs in side by side relationship driven by a vertically disposed electric motor. In such a machine the vertical shafts of the rubbing discs are provided with large driven gears meshing with each other, a small pinion gear on the end of the motor shaft being in engagement with one of the large driven gears.

Evolving from the two-disc machine, in response to production demands for higher rates of surfacing for larger expanses of area, came the four-disc machine with front and rear pairs of discs whose vertical shaft axes intersect approximately the four corners of a square. A natural evolution arrived at a vertical shaft motor, as in prior models, with a pinion on the end of the motor shaft driving a pair of gears disposed on diagonally opposite disc shafts, each of these shafts in turn having a gear meshing with a gear on the adjacent shaft to the front or rear, as the case may be, of an adjacent disc. As can be seen, there is a total of seven gears in the housing to drive the four discs from the vertical motor shaft. This, of course, is an expensive arrangement.

Then, too, the vertical type electric motor required for driving four discs is much larger than for the two-disc arrangement, and disproportionately more expensive. In addition, as power requirements increase, the selection of vertical shaft electric motors from which to choose becomes unduly limited.

Furthermore, it was known that for many cases a power source completely independent of the need for electrical feeder cables would have many advantages and offer the user a wider selection of machines to fit the requirements of the various types and sizes of surfacing jobs to be done. In other words, a gasoline engine as an alternate choice to an electric motor was indicated, but this would call for a complete redesign of basic concepts because of the horizontal output shaft of such an engine.

The present invention was conceived as the aforementioned requirements became evident. It was discovered that only four gears were required in the gear housing, forming a train with each gear on a disc shaft. One of the disc shafts extends vertically upward through the top of the housing and has disposed thereon one of the gears of a readily available and relatively inexpensive right angle drive, the other pinion gear of which is disposed on a horizontal shaft. The other end of the horizontal shaft is provided with a pulley which is coupled to the engine or electric motor mounted on and spaced above the housing. The arrangement is neat and compact with no parts of the mechanism above the housing extending to any appreciable extent beyond the front and side vertical surfaces of the housing, thus permitting the machine to work close to the walls of the particular area being surfaced. This is extremely important since it minimizes the amount of hand finishing required on the floor surfaces adjacent the walls.

One unforeseen problem was presented with the arrangement as aforesaid, and that was the uneven wear of the rubs used in surfacing the terrazzo floors. It was discovered that the location of the center of mass of the whole machine above the rubs was not always concentrated on an exact center between the axes of the rubbing disc shafts, one reason being that the engine or motor was mounted so as to be horizontally adjustable on rails, transversely of the axis of the output shaft, in order to provide takeup of the slack of the V-belts on the pulleys of the output and above-mentioned horizontal shafts. Uneven wear of the rubs is highly undesirable since it contributes to the down time of the machine when the rubs have to be replaced.

It was then conceived that auxiliary weights could be applied to the machine and could be adjustably varied as to the point of application of their mass so as to bring about uniform unit loading on the rubs on the discs. In the ultimate evolution of the concept the auxiliary weights are mounted on the ends of swing arms, the other ends of which are pivotally secured to a wheeled handling unit which has pinned connections with the gear housing on either side thereof by way of adjustable bracket fixtures. In one position of the swing arms the mass of the auxiliary weights bear on the bracket fixtures and hence on the rubs. In another position of the arms the weights provide mechanical advantage to enable the entire machine to be rotated or swung on the axis of the wheels to lift the rubs off the floor to enable changing the rubs, all as will be brought forth in detail below.

It is an object of the invention to provide a floor surfacing machine substantially as set forth above and described in detail hereinafter in connection with the drawings wherein a preferred embodiment of the invention is illustrated, and in which:

FIG. 1 is a side elevation view of a floor surfacing machine embodying the invention;

FIG. 2 is a somewhat enlarged view of a portion of FIG. 1 with parts broken away;

FIG. 3 is a top plan view of a portion of the machine taken on the line 33 of FIG. 2;

FIG. 4 is a top plan view of a portion of the machine taken on the line 4-4 of FIG. 2;

FIG. 5 is a plan view of the driving gear arrangement taken on the line 55 of FIG. 2;

FIG. 6 is a front elevation view of the machine;

FIG. 7 is an elevation view in cross-section taken on the line 77 of FIG. 6;

FIG. '8 is a fragmentary view of a portion of the machine taken on the line 88 of FIG. 1, and showing one of the bracket fixtures forming a feature of the invention;

FIG. 9 is a perspective view of the bracket fixture of FIG. 8; and

FIG. 10 is a side elevation of the machine of FIG. 1, showing it tilted back onto its handle to a position enabling changing or replacing the rubbing blocks.

Referring to FIG. 1, the floor surfacing machine 10 is shown as comprising two major assemblies, namely the surfacing unit 12 and the handling unit 14. The surfacing unit 12 comprises a support frame 16 which includes also a housing 17 for a gear train, described in detail hereinafter. Mounted on the frame 16 is a right angle drive 18, as best seen in FIGS. 3 and 7, the drive 18 including a housing 20 which houses a power transmission shaft 22 on 3 one end of which is secured the bevel pinion 24. On the other end of the shaft 22 is disposed the V-belt pulley 26.

Likewise mounted on the frame 16 is a power means shown as an internal combustion engine 28 having a pulley 30 on the end of its power output shaft. Providing a driving connection between the pulleys 26 and 30 are the V- belts 32. By this means the power of the engine is transmitted to the bevel pinion 24 which meshes with the bevel gear 34 disposed on the vertical shaft 36. The shaft 36 extends into and through the housing 17. Within the housing a gear 38 is secured on the shaft 36. On the lower end of the shaft 36 is secured the spider or rubbing disc 40 to which is secured in known fashion the abrasive blocks or rubs 42. Meshing with the gear 38 is a second gear 44 disposed on the second vertical shaft 46 in the housing 17. On the lower end of the shaft 46 is another spider 47 likewise provided with rubs 42. It will be observed that gear 44, shaft 46 and spider 47 (together with its rubs 42) is disposed to the front of the machine 12, forwardly of the gear 38, shaft 36, and spider 40 (together with its rubs 42) Referring to FIG. 5, the gear 38 is engaged by a third gear 48 which, in turn, is engaged by a fourth gear 50. Gears 48 and 50 are disposed on shafts 52 and 54, respectively, disposed in the housing 17. The lower ends of the shafts 52 and 54 are provided with spiders (not shown) similar to that shown at 40 and 47 in FIG. 7. Rubs similar to those shown at 42 are secured in the spiders on the ends of the shafts 52 and 54. There is thus formed a gear train with the gear 50 driven by the gear 48 which is driven by the gear 38 which also drives the gear 44. By the nature of things, gear 44 could also be in mesh with the gear 50. However, it is preferred that there be a slight clearance of the order of inch between the gears 44 and 50 in order to prevent any lockup of the gear train which might occur by, for example, the loss of a tooth on one of the gears.

Referring back to FIG. 1, the handling unit 14 includes a general U-shaped handle 56, the lower ends of which are secured as by welding to a tubular member 58 (FIG. 4) which encloses an axle 60, to the ends of which are secured the carriage wheels 62 and 64. Transversely disposed across the upper end of the handle 56 is a tubular cross member 66 upon which is swingably received another generally U-shaped auxiliary handle 68 which is normally disposed forwardly as shown in solid lines in FIG. 1 but which may be swung about the transverse member 66 to the dotted line position shown in FIG. 1 in order to provided mechanical advantage to tilt the entire machine about the axis of the wheels 62 and 64 to the position shown in FIG. 10 for the purpose of changing the rubs on the spiders.

The unit 14 further includes a pair of vertical channel iron risers 70 and 72 (FIG. 3) through the lower ends of which passes the axle 60. A transverse structure member 74 is secured to the upper ends of the risers 70 and 72, as by welding or any preferred method. The member 74 may be a channel iron or angle iron member, to the ends of which are secured the forwardly disposed angle iron members 76 and 78 by welding at the rearward ends of the latter.

A particular feature of the invention is the means employed to couple the surfacing unit 12 and the handling unit 14 together. To this end there is disposed upon the top surface of the housing 17 a pair of T-shaped bracket fixtures 80 and 82 secured to the housing by bolts 84 and 86, respectively. The fixtures 80 and 82 are identical, and as best seen in FIGS. 8 and 9 the fixture 80 includes a post 88 upstanding from the foot 90 which is provided with slots 92 and 94 at the front and rear ends thereof.

With this construction it is seen that the fixture 80 is adjustable forwardly or rearwardly of the housing 17 by the simple expedient of loosening the bolts 84, and likewise for the fixture 82 with respect to the bolts 86.

The fixture 80 is provided with a bolt hole 96 arranged to receive a bolt 98 which also passes through a bolt hole in the side flange 100 of the angle iron member 76, a nut 102 on the bolt 98 securing the members together, as best seen in FIG. 8. Abolt 104 secures the angle iron member 78 and the fixture 82 in similar fashion. It should be noted that when the nuts on the bolts 98 and 104 are drawn up the brackets 80 and 82 are not tightened against the flanged sides of the angle iron members 76 and 78, respectively. This arrangement permits at least limited swivelling movement of the surfacing unit 12 about the bolts 98 and 104 with respect to the handling unit 14 in order to compensate for wear and attrition of the rubs as the surfacing operation progresses.

A feature of the invention is the mass loading that may be brought to bear selectively on the surfacing unit 12. To this end there is provided a pair of swing arms 106 and 108 formed preferably from angle iron. As best seen in FIG. 4, the rear end of the arm 106 is provided with a tubular element 110 secured thereto by welding or brazing. The element 110 is disposed over a transverse rod member 112 and swingably secured thereon by a cotter pin or a nut 114, as preferred, the arm 106 thus being swingable about the axis of the member 112 between the full line and dotted line positions shown in FIG. 1. The member 112 is secured by welding to a strap 116, one end of which is welded or otherwise secured to the riser 118 of the handle 56 and the other end by a bolt 120 to the transverse structure member 74. The member 112 is similarly secured to a strap (not shown) disposed between the handle riser 122 and the structure member 74. The swing arm 108 is swingably disposed on the other end of the transverse member 112 in a fashion similar to that of arm 106. The arms 106 and 108 are independently swingable about the axis of the rod member 112.

Secured to the forward end of the arm 106 by means of bolts 124 and 126 are a pair of masses 128 and 130, respectively. The arm 108 is likewise provided with masses, one of which is shown at 132 in FIG. 6. The masses 130 and 132 are provided with hand grip handles 134 and 136, respectively, to enable ease of pivotal swing of the arms 106 and 108 about the axis of the transverse rod member 112.

Either or both of the arms 106 and 108 may be swung back in a counterclockwise direction, as viewed in FIGS. 1 and 10, by means of the handles 134 and 136, to the dotted line position shown in FIG. 1 whereat they rest against the U-shaped handle 56. When swung to that position, the load masses assist the operator to tilt the machine to the position shown in FIG. 10. When swung clockwise to rest on the angle iron members 76 and 78, the weight loading of the masses is brought to bear through the bolts 98 and 104 and the brackets 80 and 82, respectively, upon the support frame 16 and hence on the abrasive rubs 42.

As was pointed out above, an important feature of the invention is the provision of means whereby the unit load ing, between the rubs 42 and the floor being surfaced, may be adjustably varied so that the attrition of the rubs is substantially uniform. It is now seen from the foregoing description that the adjustability of the bracket fixtures 80 and 82 fore and aft by the loosening of the bolts which secure them to the support frame 16 provides the means aforesaid. Thus, with reference to FIGS. 2 and 3. loosening of the bolts 84 permits fore and aft adjustment of the fixture 80 and likewise for independent adjustment of the fixture 82 by means of the bolts 86. If, for example, during the operation of the machine it is found that the rubs on the spider or rubbing disc 47 (FIG. 7) are wearing less than those on the disc 40, the fixture 82 may be adjusted forwardly after loosening the bolts 86, after which adjustment the bolts are again tightened. It has been found, for example, in a successful working embodiment of the machine that an adjustment of Ms inch of a bracket fixture results in a net change of weight of about 20 pounds as between the total load of front and rear rubbing discs on the floor being surfaced.

By this means the wear on the rubs is made uniform, and the rubs on all four discs will last through approximately four hours of concentrated surfacing, hence need be changed only twice during a normal work day.

As a matter of usual practise, there is provided a water tank 138 secured atop straps 116 for the purpose of supplying water through a hose (not shown) to the floor area adjacent the rubs 42. A gasoline tank 140 is secured to the handle 56 by any convenient means to supply fuel for the engine 28.

We claim:

1. A floor surfacing machine comprising:

(a) a support frame;

(b) first and second driving shafts vertically and rotatively disposed on said support frame;

(c) first and second rubbing discs with abrasive rubs disposed on the lower ends of said shafts, said rubs adapted to contact a floor to be surfaced;

(d) power means on said support frame and having a driving connection with said driving shafts; and

(e) mass loading means on said support frame substantially intermediate the axes of said shafts for applying mass loading to said discs, said loading means being disposed for adjustability toward and from the axis of one of said shafts to provide adjustable variation of the unit loading on said rubs on said rubbing discs by said mass loading means.

2. The machine of claim 1 in which said loading means comprises a bracket fixture adjustably disposed on said support frame.

3. The machine of claim 2 in which said loading means further comprises a handling unit having a pivotal connection with said fixture, said loading means including a swing arm having one end pivotally connected thereto, said arm being provided with a loading mass adjacent the other end thereof and adapted to bear on said fixture in one position thereof and adapted to bear on said unit in another position thereof.

4. The machine of claim 3 in which said handling unit includes a carriage wheel engaging the floor to be surfaced, said swing arm being pivotally arranged on said unit such that in said other position thereof said loading mass provides mechanical advantage to assist rotation of said machine about the axis of said wheel to lift said rubbing discs from the fioor.

5. The machine of claim 1 in which said driving shafts are coupled together for rotation in opposite directions, said driving connection therewith comprising a horizontally disposed power transmission shaft having a gear connection with one of said driving shafts, said power means comprising a horizontal power output shaft having a driving connection with said power transmission shaft.

6. A fioor surfacing machine comprising:

(a) a support frame;

(b) first and second driving shafts vertically and rotatively disposed on said support frame;

(0) first and second rubbing discs with abrasive rubs disposed on the lower ends of said first and second driving shafts and adapted to contact a floor to be surfaced;

(d) third and fourth driving shafts vertically and rotatively disposed on said support frame;

(e) third and fourth rubbing discs with abrasive rubs disposed on the lower ends of said third and fourth driving shafts and adapted to contact a floor to be surfaced;

(f) first and second meshing gear means on said first and second driving shafts;

(g) third and fourth meshing gear means on said third and fourth driving shafts, one of said first and second gear means meshing with one of said third and fourth gear means;

(h) power means on said support frame and having a driving connection with one of said driving shafts;

(i) first mass loading means on said support frame substantially intermediate the axes of said first and second driving shafts for applying mass loading on said rubs on said first and second rubbing discs, said first mass loading means being disposed for adjustability toward and from the axis of one of said first and second driving shafts to provide adjustable variation of the unit loading on said rubs on said first and second rubbing discs by said first mass loading means; and

(j) second mass loading means on said support frame substantially intermediate the axes of said third and fourth driving shafts for applying mass loading on said rubs on said third and fourth rubbing discs, said second mass loading means being disposed for adjustability toward and from the axis of one of said third and fourth driving shafts to provide adjustable variation of the unit loading on said rubs on said third and fourth rubbing discs by said second mass loading means.

References Cited UNITED STATES PATENTS 2,774,199 12/ 1956 Emmons 51177 2,793,476 5/1957 Lombardo 51177 3,128,581 4/1964 Tosetti 51177 FOREIGN PATENTS 451,149 2/1913 France.

JAMES L. JONES, JR., Primary Examiner. 

